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    <title>Document</title>
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    <script>
        var arr = [1,2,3,4]
        // var newArr = []
        // for (var i = arr.length - 1 ; i>= 0; i--) {
        //     newArr[newArr.length] = arr[i]
        // }
        // console.log(newArr);

        arr.reverse()
        console.log(arr);
    </script>
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